Solar-Powered Water Level Sensor for Home Assistant

Overview

This is a solar-powered, wireless water level sensor designed for Home Assistant. It utilizes an ESP32-C3 Supermini and an AJ SR04M waterproof ultrasonic sensor to measure and transmit water levels. The system runs on a 1S Li-ion battery, charged via an MPPT 6V module, making it self-sufficient and maintenance-free.
This sensor has been installed and tested for over 6 months, operating reliably in real-world conditions.

Features

• Wireless & Solar-Powered – No need for constant charging or wiring.
• ESPHome-Based – Seamless integration with Home Assistant.
• Waterproof Ultrasonic Sensor – Accurately measures water levels.
• Battery Monitoring – Sends battery percentage to Home Assistant.
• Low Power Consumption – Optimized for extended battery life.
• 3D-Printed Case – Protects components from environmental damage.

Components Used

1. ESP32-C3 Supermini
2. AJ SR04M Waterproof Ultrasonic Sensor
3. MPPT 6V Solar Charging Module
4. 1S Li-ion Battery (with BMS)
5. 3D-Printed Enclosure (for weatherproofing)

Wiring Diagram - Refer to the Video

https://youtube.com/shorts/L9-_Wh9T4gA

Installation & Setup

1. Flashing the ESP32-C3

• Use ESPHome Flasher or the ESPHome add-on in Home Assistant.
• Upload the provided water-level-sensor.yaml configuration.

2. Adding to Home Assistant

• Navigate to Settings > Devices & Services.
• Click Add Integration > ESPHome.
• Enter the device name (water-level-sensor.local).
• Water level and battery percentage will now be visible in Home Assistant.

3. 3D-Printed Enclosure

A custom 3D-printed case protects the sensor and electronics from weather conditions. STL files will be available in this repository.

ESPHome Configuration

The ESPHome YAML configuration used to flash onto the ESP32-C3 Supermini is available.